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Consider an organism that has a dominant phenotype, is it possible to determine its genotype? explain your answer

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Answer:

Yes, it is possible via testcrossing

Step-by-step explanation:

The law of dominance has made it possible that a phenotype may be expressed without knowing the actual genotype (allele combination). This occurs when an allele is dominant over another allele (recessive), hence, the dominant phenotype can either be in a heterozygous or purebred state.

However, a way to discover the genotype of an organism that is portraying dominant phenotype is TEST CROSS. Test cross is the crossing of the unknown genotype with a recessive condition (will contain same recessive alleles).

After crossing, the offsprings will be used to determine whether the parent with unknown genotype is heterozygous or not.

- If the offsprings all exhibit the dominant phenotype, the unknown genotype contains the same dominant alleles e.g DD.

- If 50% of the offsprings exhibit a recessive phenotype, the unknown genotype is heterozygous e.g Dd.

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